• 물과 미래
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• 제17권2호
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• pp.72-79
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• 1984

This investagation was carried out by analyzing water types and measuring the environmetal isotopes (tritium and deuterium) for development of water resources and protection of ground waters from sea water intrusion. The water sample were taken monthly from April to June, 1983 from sixteen sites in the Cheju metropolitan area; three sea, three spring, and ten ground waters. The ground water in the midwest area of the city contained 20 TU of tritium and-46 per mille of deuterium, classified as the $NaHCO_3$ type of ground water, generally deep seated. The spring water and ground water in the southern part of the city contained 15 to of tritium and-39 per mile of deuterium, and appeared to the $CaHCO_3$ type of shallow ground water, easily affected 표 precipitation. The results of tritium and deuterium analyses showed that the ground water in the coastal area were not affected by sea water intrusion, although they changed from $NaHCO_3$ or $CaHCO_3$ type to NaCl type in May and June. It is concluded that the high Na and Cl content in those ground waters might come from municipal sewage. The sea water in the Yong-duam area was influenced by sping water.

• 대한지하수환경학회지
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• 제6권3호
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• pp.126-132
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• 1999

삼중수소는 물분자중 수소원소의 동위원소로서 물의 유동연구에 가장 이상적인 추적자로서 활용된다. 국내에서 포항지역 강수중 삼중수소 함량은 1961년-1976년까지는 IAEA에서 분석되었고. 1987년도부터 현재까지 한국원자력 연구소에서 분석하고 있다. 강수중 삼중수소함량은 핵실험의 영향으로 1963년에 1.940 TU까지 증가된 바 있으나. 그후 지속적으로 감소되어 현재는 약10TU로 핵실험이전 수준으로 낮아졌다. 이러한 삼중수소 분석결과는 지표수-지하수 상관관계 해석 및 지하수의 연대측정등 국내 수문학연구에서 매우 중요한 입력자료로 활용될 것이다. 분석결과의 신뢰성은 국제기관과의 교차분석을 통해서 확인되었다.

• Journal of Radiation Protection and Research
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• 제23권2호
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• pp.75-82
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• 1998

HTO로 피폭시키는 동안 피폭상자내 공기중의 삼중수소 농도는 트리튬 용액의 증발속도 뿐 아니라 주변환경의 영향으로 피폭시기마다 다르게 나타났다. 어린 벼의 식물 대사율은 배추의 대사율 보다 다소 높게 측정되었다. 증발된 HTO가 식물의 조직자유수에 흡수되는 정도는 배추보다 벼에서 높게 나타났다. 그러나 조직결합수의 농도는 어린 벼보다 배추에서 오히려 높게 계측되었으며 HTO 피폭 후에 조직자유수와 조직결합수의 비율은 처음에 증가하다가 시간에 따라 천천히 감소하였다. 오염된 토양에서 자라난 새로운 식물은 대부분 1보다 큰 SAR 값을 나타내었다. 피폭 약 1달 후 토양의 깊이에 따른 트리튬의 농도는 기상환경에 의해 큰 영향을 받았다.

• Nuclear Engineering and Technology
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• 제41권5호
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• pp.729-738
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• 2009

Given the evolution of High-Temperature Gas-cooled Reactor(HTGR) designs, the source terms for licensing must be developed. There are three potential source terms: fission products, actinides in the fuel and tritium in the coolant. It is necessary to provide first an inventory of the source terms under normal operations. An analysis of source terms has yet to be performed for HTGRs. The previous code, which can estimate the inventory of the source terms for LWRs, cannot be used for HTGRs because the general data of a typical neutron cross-section and flux has not been developed. Thus, this paper uses a combination of the MCNP, ORIGEN, and MONTETEBURNS codes for an estimation of the source terms. A method in which the HTR-10 core is constructed using the unit lattice of a body-centered cubic is developed for core modeling. Based on this modeling method by MCNP, the generation of fission products, actinides and tritium with an increase in the burnup ratio is simulated. The model developed by MCNP appears feasible through a comparison with models developed in previous studies. Continuous fuel management is divided into five periods for the feeding and discharging of fuel pebbles. This discrete fuel management scheme is employed using the MONTEBURNS code. Finally, the work is investigated for 22 isotope fission products of nuclides, 22 actinides in the core, and tritium in the coolant. The activities are mainly distributed within the range of $10^{15}{\sim}10^{17}$ Bq in the equilibrium core of HTR-10. The results appear to be highly probable, and they would be informative when the spent fuel of HTGRs is taken into account. The tritium inventory in the primary coolant is also taken into account without a helium purification system. This article can lay a foundation for future work on analyses of source terms as a platform for safety assessment in HTGRs.

• Korean Chemical Engineering Research
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• 제58권4호
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• pp.596-603
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• 2020

본 연구에서는 화학공정 최적화에 사용되는 생산계획최적기법을 도입하여 핵융합 공정에서의 삼중수소 재고량을 최소로 유지하는 수학적 모델을 구축하여 최적 운전 시나리오를 도출하였다. 핵융합 발전을 위한 공정 중 연료주기 공정(fuel cycle)은 반응연료인 중수소와 삼중수소를 저장 하고 공급하는 시스템과 핵융합 반응 배가스로부터 이를 회수 및 분리하는 세부 공정들로 구성되어 있다. 이들 공정들은 삼중수소가 방사성 물질이라는 것을 제외하면 대부분 촉매반응과 분리공정으로 이루어져 화공플랜트에 적용된 기술과 유사한 특성이 많아 화학공정에 사용되는 스케줄링 기법을 통해 최적 운전 시나리오를 도출 가능하다. 본 연구에서는 핵융합로의 다양한 장치의 특성을 반영해서, 펌프내부의 삼중수소량을 최소로 하는 최적 재생주기를 구하고, 구해진 최적 재생주기 결과를 반영하여 후단의 트리튬 플랜트에서의 최적 운전 시나리오를 확인해 보았다. 구축된 모델은 실제 토카막 시나리오에 적용되어 ITER 연료주기 내 공정의 연료흐름 및 밸런스 분석에 활용되었다.

• Journal of Radiation Protection and Research
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• 제32권3호
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• pp.111-115
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• 2007

원자력 발전소의 중수누출에 따른 삼중수소 농도증가에 의한 방사선 내부피폭과 이에 대한건강영향평가를 실시하였다. 전체 22명 가운데 13명에 대하여 검사를 실시하였으며, 이들의 내부피폭량은 $0{\sim}4.44\;mSv$ 였다. 일반혈액검사 중 백혈구수치의 변화를 이용하여 평가한 결과에서 결정적 영향에 대한 특이사항은 나타나지 않았으며, 생물학적 선량평가 방법을 이용한 체내피폭량은 $0{\sim}37\;mGy$로 확인되었다. 결론적으로 방사선 피폭은 허용한도를 초과하지 않았으며, 결정적 영향인 임상적 증상이 보이지 않았다. 이와 같이 의학적 징후와 선량평가 추정치와의 일치성은 사고시 특히 물리적 생물학적 선량평가가 유용함을 보여 준다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.431-435
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• 2003

Because the Tissue Bound Tritium of food irradiates the organic tissues of a man during a longer time than the Tissue Free Water Tritium, we found the ratio of labile and bound hydrogen, which is the direct source of TBT concentration, in grain such as rice and barley. Tissue free water was extracted from rice and barley sampled, adjacent to Wolsung nuclear power plants of CANDU type, by freeze-drying. Tissue bound water was taken from some of the dried samples by high-pressure combustion. The other of the samples was washed by tritium-free water for 2-3 hours, and dried again by freeze-drying. Tissue bound water was taken again from some of the second dried samples by the combustion. The extracted tissue free and bound waters were distilled and TFWT and TBT concentrations of them were counted by a liquid scintillation counter. Through alternating washing, drying and combustion until the concentration of TBT would be constant, the tritium concentration existing as bound hydrogen was found. The ratios of labile and bound hydrogen of rice and barley were determined by TR concentration, initial TBT concentration and bound tritium concentration. The ratios of bound hydrogen of rice and barley were 0.55, 0.60 relatively.

• Journal of Radiation Protection and Research
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• 제34권2호
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• pp.55-64
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• 2009

In a pressurized heavy water reactor (PHWR), radiation workers who have access to radiation controlled areas submit their urine samples to health physicists periodically; internal radiation exposure is evaluated by the monitoring of these urine samples. Internal radiation exposure at PHWRs accounts for approximately 20 $\sim$ 40% of total radiation exposure; most internal radiation exposure is attributed to tritium. Carbon-14 is not a dominant nuclide in the radiation exposure of workers, but it is one potential nuclide to be necessarily monitored. Carbon-14 is a low energy beta emitter and passes relatively easily into the body of workers by inhalation because its dominant chemical form is radioactive carbon dioxide ($^{14}CO_2$). Most inhaled carbon-14 is rapidly exhaled from the worker's body, but a small amount of carbon-14 remains inside the body and is excreted by urine. In this study, a method for dual analysis of tritium and carbon-14 in urine samples of workers at nuclear power plants is developed and a method for internal dose assessment using its excretion rate result is established. As a result of the developed dual analysis of tritium and carbon-14 in urine samples of radiation workers who entered the high radiation field area at a PHWR, it was found that internal exposure to carbon-14 is unlikely to occur. In addition, through the urine counting results of radiation workers who participated in the open process of steam generators, it was found that the likelihood of internal exposure to either tritium or carbon-14 is extremely low at pressurized water reactors (PWRs).

• Journal of Radiation Protection and Research
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• 제8권2호
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• pp.8-14
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• 1983

삼중수소의 단일 피폭과 만성피폭에 의한 한국인의 내부피복 선량을 삼단계형모델을 이용하여 계산하였다. 이 모델은 체내수분과 조직체 사이의 삼중 수소의 축적량을 잘 나타내 주는 것이다. 그 결과 삼단계형의 축적 반감기 9, 30과 450일을 사용한 단일 피폭의 총 선량은 1mCi/kg 섭취당 17.64mrad였고 이것의 97%는 체내수분에 있는 삼중수소에 의한 선량이고 나머지 3%는 조직내 삼중수소에 의한 것이다. 그리고 1 mCi/day의 삼중 수소를 섭취하는 만성 피폭의 경우, 총 선량은 85.5mrad/day이었다. 또한 본 연구에서는 한국인에 대한 최대허용 농도값을 선질계수 1을 사용하여 계산하였다. 그 결과, ICRP의 최대허용 농도값은 약 50%가량 낮게 평가되었으므로 한국인의 최대허용 농도값은 ICRP의 결과보다 약 50%높게 책정되어야만 한다.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.1991-1999
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• 2021

The response changes of the specific growth rate of Lemna minor duckweed was modeled using the logarithms of frond numbers on tritium activity concentration and gamma radiation dose from cobalt 60. The concept of average specific growth rate depends on the general exponential growth pattern, where toxicity is estimated based on the effect on the growth rate. One of the main questions of the effect of the radiation dose on duckweed is how to correlate the effect of beta radiation with the effect of any other radiation for modeling radiation on Lemna minor. Experimental data were extrapolated by utilizing the OECD guidelines. A linear relationship of absorbed dose and activity concentration was obtained for the average dependency growth rate of Lemna minor as D = (0.1257)·A^0.585. The dose rate of gamma irradiation from ⁶⁰Co increases with tritium activity dependence, on the specific growth rate of the Lemna minor duckweed. An increase in the tritium activity causes a decrease in the specific growth rate of the Lemna minor duckweed. It indicates that as the quantity of the beta radiation dose increase in Lemna minor duckweed, a higher quantity of gamma radiation will be required to cause the same effect in the specific growth rate of Lemna minor duckweed. The relation between the inhibition of the Lemna minor seedling growth and gamma and beta radiation dosage agrees roughly with that between the decrease of survival rate or fertility and dosage.