• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.250-255
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• 1997

중수로형(PHWR) 원자력발전소는 감속재와 냉각재로 중수를 사용하고 있어 방사성 수소동위원소인 삼중수소 생성량이 경수로에 비해 크며 계통내 삼중수소 축적량은 운전년수에 따라 증가하게 된다. 중수로형 원전에서 삼중수소 저감화를 위한 장기 대책으로 Tritium Removal Facility를 적용하는 경우, 우선적으로 괴려하여야 할 사항은 적절한 TRF의 용량을 결정하는 것이다. 이는 초기 시설 투자비뿐만 아니라 설비 및 운전의 신뢰도와 이용율에도 영향을 미치므로 연속운전이 가능하도록 용량을 결정하는 것이 중요하다. 이를 위해 감속재를 대상으로 삼중수소 농도 목표치, 삼중수소 농도 목표치 도달기간, 탈 삼중수소율, TRF 적용시점이 TRF 처리량과 촉매탑 높이에 미치는 영향을 분석하였다. 삼중수소 농도 목표치는 5~15Ci/kg, 도달기간은 3~8년, 탈 삼중수소율은 0.05~0.4, TRF 적용시점은 가동 후 10~20년이 적절한 것으로 확인되었다.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.633-638
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• 1998

벼의 성장시기에 다른 대기중 삼중수소의 식물채내 흡수실험을 수행하였다. 투명한 아크릴로 만들어진 피폭상자(50x60x120cm)내의 피폭조건은 비록 같은양(18.5 MBq)의 HTO를 증발시키더라도 동일한 농도를 유지하는 것이 거의 불가능하였다. 벼꽃의 매화 직후부터 수확기까지 이삭의 생성시기별로 HTO에 피폭시킨 후 잎, 줄기 및 이삭으로 구분된 시료에서 피폭 후 시간별로 조직자유수의 삼중수소 농토를 측정하였다. 조직자유수의 삼중수소 농도는 이삭에서 가장 느리게 감소하였으나 조직결합수의 삼중수소 농도는 이삭 성장이 가장 왕성한 시기에 높게 측정되었다.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.1-8
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• 2003

The periodic safety review of operational nuclear power plants requires that the plants should keep a well organized environmental monitoring program. The past records of environment monitoring data were analyzed. and the tritium concentrations of the samples in the surface and ground water around Kori site were measured. It was shown that the tritium concentrations around the Kori site were slightly higher than that of natural background. The change of background tritium concentration was estimated through a numerical modeling. Two different versions of 7 compartments model - the world and the northern hemisphere - defined in NCRP-62 were modeled for the global tritium cycling. The numerical solution of the model was obtained using a computer program, AMBER. The four cases of tritium source-terms into the atmosphere were considered. The results showed that the tritium concentration in the surface soil water was higher than that in sea water or surface stream water. Also, it was shown that the tritium produced by the interaction between cosmic rays and the gases were the major source of tritium, and the tritium produced by nuclear weapon test decreased considerably.

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.107-115
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• 1996

An electrolytic enrichment technique was used to measure low levels of tritium in seawater around the Korean peninsula. Tritium concentrations were determined for surface seawater samples collected from the East Sea, the South Sea, and the Yellow Sea. The tritium concentrations in surface seawater samples from the study area ranged from $0.12 BqL^{-1}\;to\;1.50BqL^{-1}$ with a mean value of $0.60{\pm}0.35 BqL^{-1}$. The means of the tritium concentration were $0.54{\pm}0.30 BqL^{-1}$ for the East Sea, $0.48{\pm}0.35 BqL^{-1}$ for the South Sea, and $0.77{\pm}0.32 BqL^{-1}$ for the Yellow Sea. The tritium concentrations in the sea areas did not show much difference no matter where the samples were taken. Due to the limited number and distribution of sampling points, no systematic change in tritium levels with latitude was observed. Measured tritium levels were similar to those observed in other data collected near Japan, but higher than mid-Pacific Ocean measurements.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.319-328
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• 2005

This paper describes a compartment dynamic model for evaluating the contamination level of kritium in agricultural plants exposed by accidentally released tritium. The present model uses a time-dependent growth equation of plant so that it can predict the effect of growth stage of plant during the exposure time. The model including atmosphere, soil and plant compartments is described by a set of nonlinear ordinary differential equations, and is able to predict time-dependent concentrations of tritium in the compartments. To validate the model, a series of exposure experiments of HTO vapor on Chinese cabbage and radish was carried out at the different growth stage of each plant. At the end of exposure, the tissue free water(TFWT) and the organically bound tritium(OBT) were measured. The measured concentrations were agreed well with model predictions.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.172-181
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• 2005

Collection Efficiency of a tritium bubbler being used at domestic nuclear power plants was studied. Equilibrium is attained while tritium vapour in air passes through the bubbler. When a lot of gas sample passes through the bubbler, the tritium concentration of water is raised and volume of water is decreased or increased. These phenomena give effect to the collection efficiency. Estimation of the tritium concentration of the water agreed with our experiments. If relative humidity is higher than 0.5, the efficiency becomes lower than 1 and if relative humidity is lower than 0.5, the efficiency becomes higher than 1, provided collected tritium is evaluated with original volume of the water. Though the relative humidity is riot 0.5, the efficiency can be maintained near 1 by making $\frac{saturated\; water\; vapour(cm^3_w)\times volume \; of \; gas \; sample(cm^3)}{volume\; of\; water(cm^3)}$ small

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.539-543
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• 2003

The objective of this to improve the reliability of the safety evaluation code for Wolsong Tritium Removal Facility(WTRF) which is on the development for environmental assessment. To achieve this, tritium concentrations calculated in the Wolsong Units of this study are compared with that of the existing reference. As the result, the tritium concentration in each Wolsong nuclear power plant unit just before operating WTRF is 60.9Ci/kg, 36.3Ci/kg, 30.0Ci/kg, 26.5Ci/kg under the assumption that the WTRF begins operation in 2005, respectively. This result is almost same with that of the existing reference. But the reducing rate of tritium concentration in the moderator is faster than that of the reference result Finally it is expected to drop below 10Ci/kg after WTRF operation. And this result is also similar with that of the existing reference.

• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.112-113
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• 2009

원전주변 환경방사능측정 시료 중 다른 시료와 다르게 저수지는 방사능축적 경향을 확인할 수 있는 가능성이 매우 높다. 본 논문에서는 문제해석의 단순화를 위해 여러 가정의 전제하에 원전주변 저수지의 삼중수소농도계산이 가능한 수치모델을 제안하고 그 결과를 통해 환경방사능 해석에 필요한 값들을 제공하는 방법을 제안하였다. 환경방사능 해석에 제공될 수 있는 값들로는 저수지의 삼중수소농도의 포화여부, 저수지 인근의 삼중수소 농도, 원전으로부터 삼중수소 방출율의 추정, 저수지에 대한 모니터링의 필요성 등이 포함된다.

• Analytical Science and Technology
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• v.17 no.3
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• pp.251-262
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• 2004

It is for the purpose of investigating the tritium distribution in the leachates, the raw and treated leachates and the condensates of the methane gas, which have occurred from domestic solid waste landfills. Also it aims to measure the tritium distribution level on the colloid size of the leachates, the raw and treated leachates. It was found that the major inorganic contaminants of the leachates were Na, K, Ca, Mg, $NH{_4}^+$-N and $Cl^-$. The mean tritium level of the raw leachates of the investigated 13 landfill sites for 6 months was 17 ~ 1196 TU. It corresponded to a several scores or hundreds of magnitude higher value than that of the normal environmental sample level except for two landfill sites. Also such a high concentration of the tritium was found in the treated leachates and methane gas condensates as well. Nevertheless it is important to emphasize that the tritium level which was found in this research is about 100 times lower than the tritium limit for the drinking water quality. And most of the tritium existed in the dissolved colloid of the leachate of which the colloid size is below $0.45{\mu}m$. Also, according to the tritium analysis results of the leachates after filtration with $0.45{\mu}m$ membrane filter for some landfills, it is likely that some tritium of the leachate would be distributed in a colloid size over $0.45{\mu}m$. In general the relationship between the tritium and other contaminants in the raw leachate was low, but it was relatively high between the tritium and TOC. However, the tritium content in the leachate had no meaningful relationship with the scale, hydrological characteristics and age of the landfill.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.484-490
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• 2003

The amount of the tritium released from Wolsong units during the WTRF operation is predicted. The profiles of tritium concentration in moderators and PHTs as variation of WTRF service allotment for each Wolsong unit are calculated, and the tritium releases are obtained from these tritium concentration profiles. The tritium concentration in moderator will be decreased down under 10 Ci/kg in 2013 and the yearly tritium release will be reduced below 25% of WTRF start year.