• 방사성폐기물학회지
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• 제16권1호
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• pp.11-39
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• 2018

Tritium and $^{14}C$ are two most important radionuclides released from nuclear facilities to the environment, and $^{14}C$ contributes dominant radiation dose to the population around nuclear power plants. This paper presents an overview of the production, pathway, species and levels of tritium and $^{14}C$ in nuclear facilities, mainly nuclear power plants. The methods for sampling and collection of different species of tritium and $^{14}C$ in the discharge gas from the stack in the nuclear facilities, atmosphere of the nuclear facilities and environment are presented, and the features of different methods are reviewed. The on-line monitoring methods of gaseous tritium and $^{14}C$ in air and laboratory measurement methods for sensitive determination of tritium and $^{14}C$ in collected samples, water and environmental solid samples are also discussed in detailed. Meanwhile, the challenges in the determination and speciation analysis of tritium and $^{14}C$ are also highlighted.

• Nuclear Engineering and Technology
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• 제54권2호
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• pp.469-478
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• 2022

Tritium was extracted from tritium-contaminated aluminum samples by heating it in a high-temperature furnace at 200, 300, or 400 ℃ for 15 h. The extracted tritium was analyzed by using a liquid scintillation counter (LSC); the sample thicknesses were 0.4 and 2 mm. The differences in tritium extraction over time were also investigated by cutting aluminum stick samples into several pieces (1, 5, 10, and 15) with the same thickness, and subsequently heating them. The results revealed that there are most of the hydrated material based on tritium on the surface of aluminum. When the temperature was increased from 200 or 300 ℃-400 ℃, there are no large differences in the heating duration required for the radioactivity concentration to be lower than the MDA value. Additionally, at the same thickness, because the surface of aluminum is only contaminated to tritiated water, cutting the aluminum samples into several pieces (5, 10, and 15) did not have a substantial effect on the tritium extraction fraction at any of the applied heating temperatures (200, 300, or 400 ℃). The proportion of each tritium-release materials (aluminum hydrate based on tritium) were investigated via diverse analyses (LSC, XRD, and SEM-EDS).

• Journal of Radiation Protection and Research
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• 제40권4호
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• pp.267-276
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• 2015

원전 기체 및 액체 방사성폐기물 중 가장 배출 기여도가 높은 삼중수소를 대상으로 국내 원전 가압경수로 및 가압중수로에 대해서 배출량 비교 분석과 풍향 빈도 분석, 또한 환경매체 중 삼중수소 거동 추이를 비교 분석하였다. 분석결과 먼저 기체 및 액체 삼중수소 배출량은 가압경수로보다 가압중수로에서 기체는 2013년 기준 약 10배 이상, 액체는 2배 내지 3배 정도 더 배출을 하고 있는 것을 알 수 있었다. 배출량 분석시 특이사항은 일부 원전에서 2개 호기가 배출량이 동일하게 분석된 것을 알 수 있었는데 이는 정확한 배출관리 및 분석을 위해서는 호기별 독립적인 배출관리 및 분석이 이루어져야 할 것으로 판단된다. 풍향빈도 분석은 16 방위 기준 평균 범위가 1.7~11.5%의 넓은 범위를 보였으며 풍향에 따라 환경매체 분석용 시료채취 지점을 분석해본 결과 대체적으로 풍향에 따라 잘 선정되어 있으나 일부 지점 검토가 필요한 것을 알 수 있었다. 환경매체 중 삼중수소 농도 추이 분석은 원전으로부터 거리가 가까울수록 삼중수소 농도가 높은 것을 확인할 수 있었고 가압경수로 원전의 경우는 원거리 환경매체는 극히 미미한 수준을 나타낸 반면 가압중수로 원전은 비록 원거리 환경매체라 하더라도 가압경수로 원전의 근거리 농도 수준 이상으로 월등히 많이 검출이 되고 있음을 알 수 있었다. 이렇게 가압중수로 원전에서 삼중수소 배출량이 높고 환경매체 중 삼중수소가 기준치 미만이긴 하나 검출이 되고 있으므로 계통에서의 관리 강화와 환경에서의 모니터링이 지속적으로 이루어져야 할 것으로 판단된다.

• 품질경영학회지
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• 제19권2호
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• pp.96-107
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• 1991

At the design stage of a plant, the plausible causes and pathways of release of hazardous materials are not clearly known. Thus there exist large amount of uncertainties on the consequences resulting from the operation of a fusion plant. In order to better handle such uncertain circumstances, we utilize the Probabilistic Risk Assessment(PRA) for the safety analyses on fusion power plant. In this paper, we concentrate on the tritium release accident. We develop a simple model that describes the process and flow of tritium, by which we figure out the locations of tritium inventory and their vulnerability. We construct event tree models that lead to various levels of tritium release from abnormal initiating events. Branch parameters on the event tree are assessed from the fault tree analysis. Based on the event tree models we construct influence diagram models which are more useful for the parameter updating and analysis. We briefly discuss the parameter updating scheme, and finally develop the methodology to obtain the predictive distribution of consequences resulting from the operating a fusion power plant. We also discuss the way to utilize the results of testing on sub-systems to reduce the uncertain ties on over all system.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2010년도 춘계 학술발표회 및 심포지엄
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• pp.200-201
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• 2010

• 방사선산업학회지
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• 제17권2호
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• pp.135-141
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• 2023

Tritium is used in various types of parts such as luminous bodies. These parts are maintained for inspection and replacement at a facility licensed to use radioactive isotopes. This study analyzed the concentration of tritium in working facilities to supplement and develop the safety management system for the maintenance environment of parts containing tritium. In addition, the internal exposure dose was evaluated to analyze the effects of leaked tritium when continuously exposed to workers. As a result of evaluating the internal exposure dose for workers for 30 days, the maximum was 9.70 μSv and the average was 1.45 μSv. Based on the results of this study, the internal radiation exposure safety of workers handling parts containing tritium was confirmed, and additional protective measures to prevent unnecessary exposure to tritium were suggested. This study is expected to contribute to supplementing and developing the radiation safety management system.

• 분석과학
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• 제17권3호
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• pp.251-262
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• 2004

생활폐기물을 매립, 처리하는 위생매립장에서 발생된 침출수의 삼중수소 분포 특성을 조사하기 위해 침출원수, 처리수 및 메탄가스응축수의 삼중수소 농도를 측정하였다. 또한 침출수 및 처리수의 콜로이드 크기에 따른 삼중수소의 용존특성을 조사하였다. 침출수의 주요 무기물 오염성분은 Na, K, Ca, Mg, 암모니아성 질소 및 염소이온이었다. 연구대상 매립장중 2개 매립장을 제외한 나머지 매립장의 침출수에서 환경준위보다 수십 내지 수백 배 이상 높은 농도의 삼중수소가 검출되었으며, 조사기간중 침출수의 평균 삼중수소 농도분포는 17 ~ 1196 TU였다. 메탄가스응축수 및 침출수 처리공정을 거친 처리수에서도 침출수와 비슷한 수준의 삼중수소가 검출되었다. 이와 같은 삼중수소의 농도는 삼중수소의 음용수 기준에 비해 약 100배 이상 낮은 수준임을 확인할 수 있었다. 침출수중 삼중수소는 대부분 $0.45{\mu}m$ 이하의 용해성 콜로이드에 분포되어 있었나, 일부는 $0.45{\mu}m$ 이상의 콜로이드에 분포되어 있는 것으로 추정되었다. 침출수의 삼중수소와 총유기성탄소가 상대적으로 높은 상관성을 나타내었다. 그러나 침출수의 삼중수소 농도는 매립장의 규모, 수문학적 특성 및 매립연령 등과 특별한 상관성이 없는 것으로 나타났다.

• Mass Spectrometry Letters
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• 제2권1호
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• pp.1-7
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• 2011

China's rapid economic growth has resulted in significant environmental side effects. Therefore, China has been interested in reducing her dependence on foreign oil and gas by developing technologies needed for hydrogen, in addition to her increasing energy mix of nuclear and renewable energy form, such as solar and wind power. There are three isotopes of hydrogen, i.e. protium (P or H), deuterium (D), and tritium (T). Both deuterium and tritium are important materials in nuclear fuel cycle industry. Tritium is one of the critical radioactive nuclides. Planning for and implementing contamination control as a part of normal operation and maintenance activities is an important function in any hydrogen facility, especially tritium facility. The development of hydrogen isotopes analysis is the key issues in this area. Mass spectrometry (MS) with medium (about 600) and high resolution (> 1,400) is commercially available; however, the routine analysis of hydrogen isotopes is done with low-resolution MS (< 200) in China. This paper summarizes the progress of MS measurement technology for hydrogen isotope abundance in China, focusing on our lab's research program and technical status. An analyzing method has been introduced for accurate measurement of tritium abundance in the H.D.T system by low resolution MAT-253 MS. The quotient of compression ratio coefficient is determined by building up equipment for laboratory-scale preparation of secondary standard gases and by considering the difference in sensitivity between hydrogen isotopes. The results show that the measured value is reproducible within the relative error range of 0.8% for gas samples of different tritium abundance.

• 방사선산업학회지
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• 제17권4호
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• pp.437-442
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• 2023

This study conducted a comparative analysis of dose evaluations for ingestion of animal products based on data from nuclear power plants in the Republic of Korea, using methodologies from the Republic of Korea, 'IAEA TRS-472', and 'CSA N288.1:14'. The research focused on tritium, the most significant constituent among the gaseous and liquid radioactive emissions. The combined evaluation of tritium, in the form of tritiated water (HTO) and organically bound tritium (OBT), yielded results of 1.143 μSv y^-1 for the Republic of Korea, 0.965μSv y^-1 for 'TRS-472', and 0.886μSv y^-1 for 'N288.1:14'. Despite the Republic of Korea's guidelines not considering OBT, the evaluation results for the Republic of Korea were higher compared to other methodologies. This discrepancy was attributed to the unique approach of not considering the moisture content per individual in the calculations of plant and feed concentration in the Republic of Korea and the simultaneous consideration of specific-activity model and transfer model. The study highlights the necessity of developing dose evaluation models tailored to regional characteristics and underscores the importance of including OBT in these evaluations.

• 분석과학
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• 제20권5호
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• pp.419-423
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• 2007

환경준위의 삼중수소 측정법을 확립코자 극저준위 액체섬광계수기(LSC)와 1 TU(Tritium Unit) 미만까지 측정이 가능한 전기분해 농축 장비의 특성을 연구하였다. 삼중수소의 측정한계를 알기위해 다양한 측정용기에 의한 장비의 바탕값을 조사한 결과 테프론 코팅된 폴리에틸렌 측정용기에서 1.86 cpm 수준이었으며 5 시간동안 계측할 경우 2.01 Bq/L로 17 TU의 검출한계를 얻었다. 400 mL 시료를 전기분해하여 20 mL까지 농축할 경우 0.8 TU의 검출한계를 얻었다. 전해농축시 수소와 삼중수소의 분리효율은 20 이상이었으며, 전해농축과정에 따른 삼중수소 회수율은 약 90%정도였다. NIST 삼중수소 표준시료를 사용하여 LSC의 측정효율을 검증한 결과 10 mL의 시료와 10 mL의 cocktail 용액을 사용한 경우 $28.70{\pm}0.27%$의 측정효율을 얻었다.